To increase the interest and degree of excitement of a game produced by a game machine, game images are switched or certain of their attributes such as their color are changed in time with game music, or the controller or the seat in which the player is sitting is made to vibrate.
In such a case, game sounds that are stored on an optical disk such as an ordinary compact disk are reproduced independently of the execution of the game program. To enable this in the conventional art, the time from the start of reproduction of the game sounds is obtained by counting from the game program side during the reproduction of game sounds from the compact disk, and images are generated in synchronization with the game sounds.
However, in such a method, when a fault such as sound skipping occurs during reproduction from the compact disk, that fault will not be reflected in the program counter and it will no longer be possible to synchronize the program counter and the game sounds. This causes a problem in that slippage will occur in images that ought to be generated in synchronization with game sounds.